We have coupled a Michrome microbore HPLC instrument directly to our Finnigan LCQ electrospray ionization mass spectrometers to allow us to perform on-line HPLC - mass spectrometry. We are continuing to evaluate and improve the performance of the system, and are currently evaluating the sensitivity that we can achieve with very narrow bone capillarly HPLC separations. At the same time, we are optimizing high senstivitiy MS/MS sequencing on the LCQ. Cont....